When Susan, 27, learned in 2008 that she had acute lymphoblastic leukemia (ALL) she was devastated. “It felt like being hit by a Mack truck,” she said. It wasn’t just about having to dealing with a fast-growing cancer of the white blood cells that was so overwhelming, but Susan had always planned on having a large family and her radiation and chemotherapy treatments would likely render her irreversibly infertile.
The preservation of her fertility was of utmost importance to Susan, so she decided to use ovarian tissue cryopreservation and transplantation, which involved the removing and freezing of her ovarian tissue before she underwent the aggressive treatments. When the time was right and her cancer was under control, Susan planned to undergo a second procedure to replant the tissue. This novel procedure has had moderate success, leading to 13 live births in women with lymphoma or solid tumors.
However a new study published online in Blood, the journal of the American Society of Hematology, says the method may be unsafe for leukemia patients. The study’s lead author, Marie-Madeleine Dolmans, MD and professor at the Université Catholique de Louvain in Brussels, found the frozen-thawed ovarian tissue might harbor malignant cells that could induce a recurrence of the disease after reimplantation.
“Our study provides clear evidence that cancer cells in women with acute and chronic leukemia can contaminate the ovaries," said Dolmans. “If this tissue is reimplanted in these women when they're ready to have children, there's a good possibility that the cancer will come back.”
Treatments for leukemia can affect fertility in both males and females and typically the patients are very young. According to the National Cancer Institute, 71 percent of those diagnosed with ALL are less than 35 years old, as are nearly 10 percent of those with chronic myelogenous leukemia (CML). In 2010, it is estimated that 2,180 women will be diagnosed with ALL and 2,070 with CML.
The goal of the Brussels study was to examine the safety of using ovarian tissue cryopreservation to safeguard the fertility of patients with leukemia.
Researchers examined the implications of the technique in 12 women with ALL, a fast-growing cancer, and six women with CML, a slowly progressing bone marrow cancer. The 18 patients included in this study were between two and 31 years of age when their ovarian tissue was cryopreserved (from 1999 to 2008). The mean age of the patients with ALL was 14.5 years and 24.7 years for those with CML.
Although initial microscopic examination did not reveal any cancerous cells in the ovarian tissue samples collected from each patient, by using a technique called real-time quantitative polymerase chain reaction (RT-qPCR) to target specific DNA molecules, the scientists found cancerous cells in the ovarian tissue of 70 percent of the ALL patients and 33 percent of the CML patients.
For further analysis, the researchers engrafted the ovarian tissue samples into 18 healthy mice for an observational period of six months. In the mice receiving tissue from CML patients, the grafts looked normal and did not appear to contain any cancerous cells. In contrast, four of the mice receiving ovarian tissue from ALL patients developed tumors.
The researchers say, given these results, further research is needed to develop safer options for fertility preservation in patients with acute and chronic leukemia.
Brandon Hayes-Lattin, MD, an Adolescent and Young Adult Oncologist at Oregon Health and Science University in Portland, agrees. “Leukemia patients can benefit from fertility preservation techniques, but the strategies offered must be both effective and safe.”
Lynette Summerill is an award-winning writer who lives in Scottsdale, Arizona. In addition to writing about cancer-related issues, she writes a blog, Nonsmoking Nation, which follows global tobacco news and events.
Source: “Reimplantation of cryopreserved ovarian tissue from patients with acute lymphoblastic leukemia is potentially unsafe.” Blood First Edition Paper, prepublished online July 1, 2010; DOI 10.1182/blood-2010-01-265751. Blood, 1 July 2010, Vol. 0, No. 2010, pp. 201001265.